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Accounts of Chemical Research     Full-text available via subscription   (Followers: 281)
ACS Combinatorial Science     Full-text available via subscription   (Followers: 9)
Acta Analytica     Hybrid Journal   (Followers: 7)
Advances in Analytical Chemistry     Open Access   (Followers: 20)
American Journal of Analytical Chemistry     Open Access   (Followers: 27)
Analytica Chimica Acta     Hybrid Journal   (Followers: 33)
Analytical and Bioanalytical Chemistry     Hybrid Journal   (Followers: 28)
Analytical Chemistry     Full-text available via subscription   (Followers: 395)
Analytical Chemistry Insights     Open Access   (Followers: 16)
Analytical Letters     Hybrid Journal   (Followers: 10)
Analytical Spectroscopy Library     Full-text available via subscription   (Followers: 10)
Annual Review of Analytical Chemistry     Full-text available via subscription   (Followers: 9)
Biomonitoring     Open Access  
Chinese Journal of Analytical Chemistry     Full-text available via subscription   (Followers: 3)
Combinatorial Chemistry - an Online Journal     Open Access   (Followers: 2)
Comprehensive Analytical Chemistry     Full-text available via subscription   (Followers: 5)
Critical Reviews in Analytical Chemistry     Hybrid Journal   (Followers: 25)
Current Analytical Chemistry     Hybrid Journal   (Followers: 6)
Drug Testing and Analysis     Hybrid Journal   (Followers: 5)
Electroanalysis     Hybrid Journal   (Followers: 4)
Field Analytical Chemistry and Technology     Hybrid Journal   (Followers: 5)
Handbook of Analytical Separations     Full-text available via subscription   (Followers: 1)
Handbook of Thermal Analysis and Calorimetry     Full-text available via subscription  
International Journal of Analytical Chemistry     Open Access   (Followers: 20)
International Journal of Chemical and Analytical Science     Full-text available via subscription   (Followers: 4)
International Journal of Environmental Analytical Chemistry     Hybrid Journal   (Followers: 6)
International Journal of Polymer Analysis and Characterization     Hybrid Journal   (Followers: 5)
ISRN Analytical Chemistry     Open Access   (Followers: 16)
ISRN Chromatography     Open Access   (Followers: 2)
Journal of Analytical & Bioanalytical Techniques     Open Access   (Followers: 5)
Journal of Analytical Atomic Spectrometry     Full-text available via subscription   (Followers: 9)
Journal of Analytical Chemistry     Hybrid Journal   (Followers: 16)
Journal of Electroanalytical Chemistry     Hybrid Journal   (Followers: 4)
Journal of Essential Oil Research     Hybrid Journal   (Followers: 3)
Journal of Radioanalytical and Nuclear Chemistry     Hybrid Journal   (Followers: 3)
Journal of Thermal Analysis and Calorimetry     Hybrid Journal   (Followers: 18)
Main Group Metal Chemistry     Full-text available via subscription   (Followers: 1)
Microchemical Journal     Hybrid Journal   (Followers: 3)
Nigerian Journal of Chemical Research     Full-text available via subscription  
Phytochemical Analysis     Hybrid Journal   (Followers: 1)
Polish Journal of Chemical Technology     Open Access   (Followers: 1)
Reviews in Analytical Chemistry     Full-text available via subscription   (Followers: 7)
Sample Preparation     Open Access  
Surface and Interface Analysis     Hybrid Journal   (Followers: 14)
Techniques and Instrumentation in Analytical Chemistry     Full-text available via subscription   (Followers: 6)
TrAC Trends in Analytical Chemistry     Full-text available via subscription   (Followers: 20)
Trends in Environmental Analytical Chemistry     Hybrid Journal   (Followers: 1)
Vibrational Spectroscopy     Hybrid Journal   (Followers: 8)
World Journal of Analytical Chemistry     Open Access  
Journal Cover   Journal of Analytical Chemistry
  [SJR: 0.33]   [H-I: 19]   [18 followers]  Follow
   Hybrid Journal Hybrid journal (It can contain Open Access articles)
   ISSN (Print) 1608-3199 - ISSN (Online) 1061-9348
   Published by Springer-Verlag Homepage  [2302 journals]
  • Development and validation of a rapid derivative spectrophotometric method
           for simultaneous determination of acetaminophen, ibuprofen and caffeine
    • Abstract: Abstract A zero-crossing derivative spectrophotometric method was used for the simultaneous determination of acetaminophen, ibuprofen and caffeine. The derivative spectra of standard solutions of each compound were obtained at different orders to find out the suitable zero-crossing points. Under the optimized conditions, determination of acetaminophen was performed at wavelengths of 311 and 270 nm using the third order (Δλ = 24.5) and fourth order (Δλ = 12.0) derivative spectra, respectively. Ibuprofen and caffeine were determined at wavelengths of 235 and 300 nm using the second order (Δλ = 21.0) and fourth order (Δλ = 27.0) derivative spectra. The method was found to be linear (r 2 > 0.998) in the range of (μg/mL) 5–50 for acetaminophen, 5–30 for ibuprofen and 1–7 for caffeine in the presence of other compounds. The within-day and between-day precision and accuracy of the proposed method were acceptable (CV < 3% and error < 2%) for all three components and the proposed method was satisfactory for quality control purposes. The method was successfully applied to the simultaneous determination of acetaminophen, ibuprofen and caffeine in pharmaceutical dosage forms without any interference from excipients and there was no need to any prior separation before analysis.
      PubDate: 2015-03-01
  • 1,2-Naphthoquinone-4-sulfonic acid sodium salt as a reagent for
           spectrophotometric determination of rimantadine and memantine
    • Abstract: Abstract A selective ultraviolet and visible spectrophotometric method (UV-Vis) for the determination of memantine (MM) and rimantadine (RM) hydrochlorides after derivatization with 1,2-naphtoquinone-4-sulfonic acid sodium salt (NQS) and extraction with dichloromethane was developed and optimized. The reaction of the NQS (0.7%, w/v solution) with memantine was carried out for 40 min in a buffer medium of NaOH/KCl (pH 12.0) at 80°C. A mixture of NQS (0.2%) and rimantadine was heated for 20 min at 50°C, in a medium of NaOH/KCl (pH 12.0). The linearity of the determinations of MM (0.05–0.60 mg/mL) and RM (0.05–0.30 mg/mL) was evaluated. LOD (28 mg/mL for MM, 11 mg/mL for RM) and LOQ (84 mg/mL for MM, 32 mg/mL for RM) values and parameters of precision and accuracy were determined. The UV-Vis method for the determination of rimantadine hydrochloride tablets was validated (selectivity, linearity, precision, accuracy).
      PubDate: 2015-03-01
  • Reduced graphene oxide in the construction of solid-state
           bromide-selective electrode
    • Abstract: Abstract To improve the electrochemical performance of solid-state printed electrodes, reduced graphene oxide is used as an intermediate layer (mediator) between the surface layer of a current collector and the ionophore layer. A graphene oxide film was deposited onto the surface of printed electrodes by drop-casting, followed by reduction and electrochemical deposition. An ionic liquid 1,3-dihexadecylimidazolium bromide served as ionophore. The effect of reduced graphene oxide on the characteristics of the ion-selective electrode is studied, and it is shown that the sensors electrochemically modified with reduced graphene oxide have the best performance. These sensors exhibit a stable, well-reproducible response to bromide ions with the slope of the electrode function close to the Nernstian value (−60.7 ± 0.7 mV/dec) and a low detection limit of 3.6 × 10−6 M. The response time for all of the electrodes does not exceed 15 s even in dilute solutions.
      PubDate: 2015-03-01
  • TLC determination of piroxicam, tenoxicam, celecoxib and rofecoxib in
           biological material
    • Abstract: Abstract A rapid, sensitive and accurate TLC method has been developed for estimation of various pharmaceutical agents, such as piroxicam, tenoxicam, celecoxib and rofecoxib in human whole blood and urine. TLC analysis was performed on silica gel F254 plates with ethyl acetate-toluene-butylamine (2 : 2 : 1, v/v/v) and chloroform-acetone-toluene (6 : 2.5 : 1, v/v/v) as mobile phases. Densitometric scanning was performed at 254, 301 and 370 nm. The method was validated in terms of linearity, accuracy, precision, sensitivity and selectivity. The response was a linear function of concentration in the range of 1.4–39.1 μg/mL (r = 0.99). Precision of the assay was in the range 0.5–1.8%, and average accuracy was close to 100%. Presented method can be applied to routine quantification studies of chosen drugs in biological material.
      PubDate: 2015-03-01
  • Quantitative digital 2D densitometry in the processing of series of
           autoradiographic images
    • Abstract: Abstract Previously we have shown that, using the mathematical pixel-by-pixel processing of a series of autoradiographic images of activated samples, analyst can gain information on the distribution of elements in geochemical samples, including large ones. The level of reproducibility in 2D densitometry is the key factor determining the efficiency of such processing. A procedure is developed for obtaining a series of digital autoradiograms using both classical nuclear photodetectors and digital imaging plates; the reproducibility of the results of quantitative densitometry was no worse than 2%. The results obtained on mapping well agree with the data of scanning electron microscopy.
      PubDate: 2015-03-01
  • A graphene-based electrochemical sensor for sensitive determination of
    • Abstract: Abstract An electrochemical sensor based on the electrocatalytic activity of graphene for sensitive detection of cyanazine (CZ) is presented. Graphene is ideally suited for electrochemical applications due to its large electrical conductivity, large surface area and unique heterogeneous electron transfer rate. Electrochemical measurements were performed at glassy carbon electrode (GCE) which was modified with graphene via drop-casting method. Cyclic voltammogram of ferri/ferrocyanide redox couple at graphene modified electrode showed an increased current intensity compared with glassy carbon and graphite modified electrode. The decrease of charge transfer resistance was also analyzed by electrochemical impedance spectroscopy. The morphology of the modified graphene electrode was characterized using scanning electron and atomic force microscopic techniques. Under the optimized experimental conditions, the proposed electrochemical sensor exhibited a rapid response to cyanazine with a linear calibration plot ranging from 0.55 to 1500 nM and a detection limit of 0.25 nM. The applicability of graphene/GCE for the determination of CZ in real samples such as tape water, river water and ground water, were checked by differential pulse voltammetry method.
      PubDate: 2015-03-01
  • Preconcentration of tetracycline antibiotics on a hyper-crosslinked
           polystyrene and their determination in waters by high-performance liquid
    • Abstract: Abstract The possibility of using hyper-crosslinked polystyrene for the dynamic sorption preconcentration (solid-phase extraction) of tetracycline antibiotics (tetracycline, oxytetracycline, chlortetracycline, and doxycycline) from aqueous solutions has been studied. The conditions of the preconcentration of tetracyclines on a microcolumn filled with hyper-crosslinked polystyrene have been optimized. The compounds were desorbed with 2 mL of an acetonitrile-methanol mixture and determined in the eluate by reversed-phase HPLC with an amperometric detector. With preconcentration the limits of detection for tetracyclines were reduced by 90–100 times. The limits of detection were 0.6 ng/mL for oxytetracycline and tetracycline, 1 ng/mL for chlortetracycline, and 2 ng/mL for doxycycline. The method has been used for the analysis of model mixture based on river water.
      PubDate: 2015-03-01
  • A combination of microextraction separation, preconcentration, and
           spectrophotometric detection for the determination of sodium dodecyl
           sulfate with quinaldine red
    • Abstract: Abstract The optimal conditions for the microextraction separation, preconcentration, and spectrophotometric determination of sodium dodecyl sulfate (SDS) as an ion associate with quinaldine red are determined. The best extractants were found to be the mixtures of CCl4 with dichloroethane or chloroform; they ensure a 10- to 50-fold preconcentration of SDS from an aqueous medium into an organic microextract. We used cuvettes of special design to measure the absorbance of microextracts. A procedure for the extraction-spectrophotometric determination of anionic surfactants with the detection limit for SDS of 0.04 μg/mL is developed. The procedure was tested using wastewater samples.
      PubDate: 2015-03-01
  • Voltammetric determination of copper with proton pump inhibitor drug
    • Abstract: Abstract The electrochemical behavior of copper(II)-omeprazole complex was studied by differential pulse and cyclic voltammetry at a hanging mercury drop electrode. A well-defined voltammetric peak was obtained at −0.6 V (vs. Ag/AgCl sat’d KCl) in phosphate buffer (pH 7). The experimental results show that the reduction of the copper(II)-omeprazole complex is irreversible. The stoichiometry and stability constant of the Cu(II)-omeprazole complex were evaluated using differential pulse cathodic adsorptive stripping voltammetry and found to be 1 : 2 and 1.39 × 1011 M−1. The limits of detection and quantitation were found to be 3 × 10−9 and 1 × 10−8 M, respectively. The proposed procedure was successfully applied for the determination of trace level of copper in bottled natural drinking water samples.
      PubDate: 2015-03-01
  • Three-dimensional viewed validated diode array UV-LC method for estimating
           dopamine in liposomes
    • Abstract: Abstract A new, sensitive, selective, rapid and validated high throughput liquid chromatographic method has been developed to estimate dopamine (DA) in bulk and formulations. Efficient chromatographic separation was achieved using a C18 reverse phase column with simple mobile phase combination, consisting of phosphate buffer (10 mM KH2PO4, pH 4.0) and methanol (96 : 4), delivered at 1 mL/min flow rate in an isocratic mode and quantitation was carried out using Photo Diode Array (PDA) detector. This method utilizes green chemistry approach in mobile phase optimization with less than 5% organic phase and only 10 min to run each sample. Thus our method is environmentally friendly. The method has demonstrated excellent linearity over the range of 25–2000 ng/mL (regression equation: average peak area (mV s) = 72.091c (ng/mL) + 141.77, r 2 = 0.9997). Moreover, the method was found to be sensitive with a low limits of detection (7 ng/mL) and quantitation (21 ng/mL). The method has shown good and consistent recoveries of 99.13–100.95% with low intra- and inter-day relative standard deviation (RSD) ≤ 2.0%. Further, this method has demonstrated good stability of DA with antioxidants for longer period. Experimental design confirmed that peak area was unaffected by small changes in critical factors, in robustness study. The method was validated as per the International Conference on Harmonization (ICH) and United States Pharmacopoeia (USP) guidelines and successfully applied to the determination of dopamine in commercial and in-house prepared liposomal formulations.
      PubDate: 2015-03-01
  • A novel technique for the determination of propylthiouracil with sodium
           nitroprusside as a chromogenic reagent by spectrophotometry
    • Abstract: Abstract A new method for the determination of propylthiouracil by spectrophotometry using sodium nitroprusside as a chromogenic reagent is described. The experiment indicated that a turquoise product could be formed by the reaction between propylthiouracil and sodium nitroprusside in basic solution. The mole ratio of propylthiouracil and sodium nitroprusside in the product is 1 : 3. The maximal absorption wavelength (λmax) of the product is 680 nm, the molar absorption coefficient (ɛ680) 1.20 × 103 L/(mol cm). Lambert-Beer’s law is obeyed in the range of 0.5–55.0 μg/mL. The linear regression equation is A = 0.00479 + 0.00705c (μg/mL), with a correlation coefficient of 0.9991. The recoveries are obtained from 96.6 to 102.3%. The proposed method was successfully applied to determine propylthiouracil in pharmaceutical samples with satisfactory results.
      PubDate: 2015-03-01
  • Determination of phenolic acids and a flavonoid in Eleusine coracana (L.)
           by semi-preparative HPLC photo diode array detector
    • Abstract: Abstract Semi preparative HPLC procedure is proposed for the determination of six phenolic acids and one flavonoid in Eleusine coracana (L.) with gradient elution and photodiode array detection. The influence of composition of the mobile phase concentration of the mix modifier and temperature on the separation of gallic acid, p-hydroxybenzoic, vanillic, caffeic, ferulic, and cinnamic acids and quercetin for 90 min is studied. The procedure was applied for the separation of phenolic compounds in methanolic extracts of Eleusine coracana (L.). The lower limits of quantification of phenolic compounds and the flavonoid are 0.050–0.150 μg/mL.
      PubDate: 2015-03-01
  • Application of cinnamoyl derivative as a new ligand for dispersive
           liquid-liquid microextraction and spectrophotometric determination of
    • Abstract: Abstract The method is based on the reaction of Co(II) with 3-[4-(dimethylamino)cinnamoyl]-4-hydroxy-6-methyl-2H-pyran-2-one (ligand) and a dimethylindocarbocyanine dye, followed by dispersive liquid-liquid microextraction of the ion associate formed and subsequent spectrophotometric detection. The appropriate experimental conditions were found to be: pH 9, 0.14 mM dye, toluene (extraction solvent) containing 2.25 mM of ligand, acetonitrile (dispersive solvent) and carbon tetrachloride (auxiliary solvent). Beer’s law is obeyed in the range 0.06–0.42 mg/L of Co(II) at a wavelength of 558 nm. The limit of detection, calculated as three times the standard deviation of the blank test (n = 10), was found to be 9 μg/L for Co(II). The method was applied to the determination of cobalt in spiked water samples and a vitamin B12 pharmaceutical injection.
      PubDate: 2015-03-01
  • A test strip for lead(II) based on gold nanoparticles multi-functionalized
           by DNAzyme and barcode DNA
    • Abstract: Abstract A simple, rapid, sensitive and selective test strip for the detection of lead(II) in water samples was developed. This method is based on gold nanoparticles multi-functionalized by 17E-17DS duplex and barcode DNA, AuNPs@(17E-17DS duplex & barcode DNA). The complex of 17E and 17DS (duplex) was constructed by the hybridization between 17E DNAzyme and its corresponding 17DS cleavage substrate. Because 17E DNAzyme has high specificity for lead(II), the presence of lead(II) induces 17E DNAzyme to specifically cleave 17DS. A barcode DNA complementary to the capture DNA was employed to reduce the amount of 17E-17DS duplex used and increase the capture probability of cleaved AuNPs@(17E-17DS duplex & barcode DNA) conjugates, and thus effectively improve the detection sensitivity. The test results for lead(II) could be visually obtained within 10 min without any instrument and sample pretreatment, with a detection limit 20 nM. In addition, the selectivity of this sensing system was investigated by challenging the sensor with other divalent metal ions, and no significant interference was found. Therefore, the developed test strip could be a potential on-site screening tool for the rapid detection of lead(II).
      PubDate: 2015-03-01
  • Statistical discrimination of black ballpoint pen inks using
    • Abstract: Abstract The aim of this study is to propose an approach for the analysis of black ballpoint pen writing inks based on ultra-performance liquid chromatography (UPLC) combined with principal component analysis (PCA). A total of twelve varieties of black ballpoint pens available in the Malaysian market were examined by an UPLC that coupled with a photodiode array detection (PDA). Chromatograms of ink samples were extracted at 279, 370 and 400 nm. Chromatographic data obtained were subjected to PCA after normalization. Seven principal components were produced from a total of 15 raw peaks. The new set of variables was then used for running one-way ANOVA to differentiate 66 pen-pair formed from twelve varieties of black ballpoint pen. The approach proposed here has successfully differentiated all pen-pair thus achieving 100% discrimination power.
      PubDate: 2015-03-01
  • Oils and grease determination by FT-IR and n -hexane as extraction solvent
    • Abstract: Abstract Recently FT-IR spectroscopy has enjoyed renewed interest for detection and quantification of contamination by oils and grease (OG), especially in water samples. This is due to the development of a new approach using less harmful solvents. This paper presents the development of a new FT-IR method that uses n-hexane as a substitute to Freon 113 in the extraction process. This solvent has a high solubility for the desired organic compounds, low miscibility with water and a low boiling point to facilitate its removal from the extracted material. Results regarding the calibration curves, recovery, precision, detection and quantitation limits are presented. Even if the recovery is not too high (45%), the preconcentration factor of 2 × 103 permits the detection of OG at levels >83 μg/L.
      PubDate: 2015-03-01
  • Combination of solid phase extraction based on nano alumina and
           liquid-liquid extraction for selective determination of palladium in food
    • Abstract: Abstract A new simple and reliable method for rapid and selective extraction and determination of trace Pd(II) was developed. Combination of solid phase extraction (SPE) and liquid-liquid extraction (LLE) of trace amounts of palladium in food and water samples has been done successfully. By coupling of SPE with LLE, advantages of both can be combined including high extraction recovery and preconcentration factor (PF), environmental friendliness, low cost and appropriate time of analysis. All conditions for SPE and LLE were optimized in order to reach high PF and extraction recovery. The metal ion was eluted completely with 1.5 mL 2 M HClO4 in acetylacetone and measured by flame atomic absorption spectrometry (FAAS). The optimum experimental conditions such as pH, sample volume, amount of sorbent and concentration of eluent on the sorption of Pd(II) were evaluated. Under the optimized conditions, the sorption capacity of the modified nano-γ-alumina for Pd(II) was 13.5 mg/g. Preconcentration from 200 mL sample solution permitted a preconcentration factor of 266. The limit of detection of this method for Pd(II) was 0.2 μg/L and the relative standard deviation (RSD) of 100 ng/mL of Pd(II) was 2.3% (n = 10).
      PubDate: 2015-03-01
  • Determination of three phenylphenols in grapefruit juice by HPLC after
           pre-column derivatization with 4-fluoro-7-nitro-2,1,3-benzoxadiazole
    • Abstract: Abstract o-Phenylphenol is generally utilized as a disinfectant for citrus fruits. The purpose of this study is to develop a high-performance liquid chromatography coupled with ultraviolet detection (380 nm) method for simultaneous determination of o-phenylphenol, and its analogues (m-phenylphenol and p-phenylphenol) in grapefruit juice after pre-column derivatization with 4-fluoro-7-nitro-2,1,3-benzoxadiazole (NBD-F). 2-Hydroxyfluorene was used as an internal standard (IS). Standard curves were obtained after derivatization with NBD-F in borate buffer (pH 8.0) at room temperature for 5 min. The three NBD-F derivatives were almost completely separated on a Cholester column (5 μm, 3.0 mm i.d. × 150 mm). Calibration plots were linear in the range of absolute amount of 1.04 ∼ 2.08 to 41.6 ng/50 μL injection volume, with r 2 values ≥0.9981, for the three compounds. The lower limits of detection were 0.3 to 0.7 ng/50 μL injection volume (signal-to-noise ratio of 3 : 1). The coefficients of variation were less than 11.1%. After extraction of grapefruit juice (2.0 mL) with n-pentane, the level of o-phenylphenol in the juice was estimated to be 20.2 ± 2.0 ng/mL (n = 6, mean ± SD), while m-phenylphenol and p-phenylphenol were below the lower limits of quantification. The recovery values of the three phenylphenols from samples spiked with a standard mixture of authentic compounds and IS were satisfactory (99.1 to 118.7%).
      PubDate: 2015-03-01
  • Molecularly imprinted inorganic supports in high-performance liquid
           chromatography and solid-phase extraction
    • Abstract: Abstract Selective preconcentration of analytes or groups of similar analytes is often useful in the analysis of biological and environmental samples and other samples of complex composition. The problem of the selective recognition of analytes can be solved using the method of molecular imprinting, which is gaining wide acceptance as an alternative to the use of biological recognition agents, for example antibodies, and favors overcoming the shortcomings inherent to the last named ones. The use of molecularly imprinted materials as adsorbents for solid-phase extraction and high-performance liquid chromatography ensures an increase in the selectivity of analyte determination in complex matrixes. This paper is a review of methods for the preparation of molecular imprints on the surface of inorganic matrixes, including nanostructured ones, and of the applications of these materials to chemical analysis.
      PubDate: 2015-03-01
  • Advances in thermal lens spectrometry
    • Abstract: Abstract The main examples of the application of thermal lens spectrometry and thermal lens microscopy as highly sensitive power-based thermooptical (photothermal) methods of molecular absorption spectroscopy to photometric, chromatographic, and electromigration methods of analysis and to solving problems related to the use of microfluid chips are considered. The fundamentals and characteristics of the thermooptical methods and instruments and the problems and prospects of their development are discussed. Examples are provided for illustrating the sensitivity and selectivity of combined methods and multidisciplinary studies performed with the aid of thermal lens spectrometry.
      PubDate: 2015-03-01
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